Adding the migration helper from Ben Wyrosdick.

CHANGELOG

@@ -1,6 +1,8 @@
 2.0 (2-17-2008)
-    * [Marshall Roch] - Stamping can be temporarily turned off using the 'without_stamps' class
-                        method. 
+    * [Ben  Wyrosdick] - Added a migration helper that gives migration scripts a <tt>userstamps</tt>
+                         method.
+    * [Marshall Roch]  - Stamping can be temporarily turned off using the 'without_stamps' class
+                         method. 
       Example:
         Post.without_stamps do
           post = Post.find(params[:id])

init.rb

@@ -1,3 +1,4 @@
 require 'stamper'
 require 'stampable'
-require 'userstamp'
+require 'userstamp'
+require 'migration_helper'

lib/migration_helper.rb

@@ -0,0 +1,19 @@
+module Ddb
+  module Userstamp
+    module MigrationHelper
+      def self.included(base) # :nodoc:
+        base.send(:include, InstanceMethods)
+      end
+
+      module InstanceMethods
+        def userstamps(include_deleted_by = false)
+          column(Ddb::Userstamp.compatibility_mode ? :created_by : :creator_id, :integer)
+          column(Ddb::Userstamp.compatibility_mode ? :updated_by : :updater_id, :integer)
+          column(Ddb::Userstamp.compatibility_mode ? :deleted_by : :deleter_id, :integer) if include_deleted_by
+        end
+      end
+    end
+  end
+end
+
+ActiveRecord::ConnectionAdapters::TableDefinition.send(:include, Ddb::Userstamp::MigrationHelper)